Today's Building Automation Systems (BAS's) are usually being specified and designed using a common open serial communication protocol. Two of the most-used serial communication protocols are (LON) Local Operating Network and (BACnet) Building Automation and Control Networking. The present invention comprises an intelligent power node comprising a JAVA-enabled device and serial communication cable that provide a seamless open protocol and aggregation point to broadcast internet protocol communications. In addition, the present invention enables energy monitoring and control of individual ports and outlets and comprises: wired/wireless universal, integrated inputs and outputs, and fault detection diagnostics; surge/noise-harmonic suppression; USB ports; RS-485/232 ports; extensible memory; IP addressability; and Power-over-Ethernet capabilities.
The following terms are useful for understanding embodiments of the present invention:                JAVA: Java is a programming language and computing platform first released by Sun Microsystems in 1995. It is the underlying technology that powers state-of-the-art programs including utilities, games, business, building automation controls, and gateway applications.        Gateway: A gateway in some embodiments of the present invention uses JAVA software to normalize both IP and serial communication data to integrate the data to be used in other systems. The normalized data points can be correlated, logged, incorporated into trend or history reports, and alarmed, with the capability for providing read/write commands to each point. This gateway in some embodiments of the present invention will have extensible internal memory and be IP-addressable using thin client access.        Integration: Integration is the process of linking disparate software systems such as, HVAC, lighting, energy, card access, and fire/life/safety systems to become part of a larger system. Integrating these disparate systems with different communication protocols using middleware allows data exchange from and between these systems.        
BAS systems are usually built and designed using one serial communication protocol (e.g., LON or BACnet). In the event that LON and BACnet are to co-exist in a BAS system it requires the use of a gateway to normalize the BAS data. Limiting a BAS system to communicate on either LON or BACnet serial communication can cause the end-user/owner problems with system scaling and being stuck with proprietary software and services, resulting in increased total cost of ownership.
BACnet
BACnet Description
BACnet is a data communication protocol for building automation and control networks. BACnet is an ISO/ANSI/ASHRAE 135-1995 standard. Like the LonWorks protocol, it has many physical/data-link layers including RS-485, Ethernet, ARCNET, RS-232, IP, and LonTalk. The BACnet (Building Automation and Control Networking) standard protocol was conceived, developed and maintained by a consortium of industry stakeholders in partnership with the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). BACNet uses a tiered network topology for communication.
A BacNet Network is a top down solution that is focused on Human Machine Interface (HMI) integration to increase interoperability. BACnet, is accepted in a variety of industries: HVAC, security, fire/life safety, lighting, etc.
LON
LonWorks Description
Local Operating Network (LON) Works uses ANSI/EIA 709.1-A-1999 as a protocol specification, and in some cases RS-485 as the electrical specification. LonTalk Protocol may be employed over twisted pair, power line (powered or un-powered), radio frequency, coaxial cabling, or fiber optics.
Speeds using different interfaces include:                Transformer Coupled at 78 kbps to 1400 meters        Transformer Coupled at 1.25 Mbps to 130 meters        Free Topology at 78 Kbps to 500 meters        Power Line at 10 kbps to 6000 meters        Radio at 15K, Line of sight [400-470 MHz and 900 MHz].        
LON (Local Operating Network) protocol was developed by Echelon Corp. LON is embedded on the neuron chip, which was designed by Echelon and is manufactured by Cypress Semiconductor and Toshiba. Any LonTalk-based device is a LonWorks device. All LonWorks devices use the neuron chip. LON uses a peer to peer (P2P) topology for communication.
How LON & BACnet are Different
LON and BACnet are very different and in many ways not directly comparable. For example, BACnet is a specification for supervisory system interoperability. The BACnet specification is designed for interoperability among computers, not devices. BACnet is implemented as a gateway solution with computers tying together disparate building subsystems.
LON certification, in contrast, pertains to devices. Yet systems based on the LonWorks platform, utilizing LonMark products, are used at the both the supervisory and device level in applications worldwide. Further, LonMark devices are certified to interoperate at the device level in a distributed architecture, wherein nodes on the network are ‘peers.’ Therefore, a system using LonMark devices doesn't need gateways, routing, or arbitration of network traffic among various subsystems, nor is it limited to HVAC systems only.
Serial Communication
Serial communication between electronic devices faces three challenges: speed, distance, and the ability to operate in an electrically noisy environment. The ability for multiple devices to share the same communication channel is also a desirable feature. As the requirements and the capabilities of the electronics industry have evolved, the new standards have been introduced to meet them.
RS-485 was designed to allow multiple electronic units to be connected to a single communications channel. RS-485 transmitters can be placed in a high impedance state and only enabled onto the channel when data must be transmitted. Simultaneous transmissions will result in the message being lost, and possibly the destruction of the drivers.
A channel can be configured for “full duplex” or “half duplex” operation. In full duplex the transmitting device can support data reception at the same time as transmission. To achieve this, RS-485 requires 2 data wire pairs, one for transmission and the other for reception. In half duplex operation the transmitter first sends its data, then it disables its driver and waits for the reply. This allows the use of a single data pair for bidirectional communication.
The RS-485 specification also allows for up to 32 unit loads to be placed on a channel. This is also known as “multidrop/field bus drop” configuration. This normally requires some method of “addressing” each module, but once again that level of protocol is outside the scope of RS-485. A “unit load” is somewhat similar to the telephone standard load. It places a limit on the number of devices that can communicate on the channel. If a device loads the channel by more than a single unit load the number of “drops” is reduced. There are devices that present one quarter of a unit load allowing up to 128 drops but the maximum communication speed is reduced.